Oct. 14, 2011 -- Many women continue to be sexually active after menopause and most say they are satisfied with their sex lives, particularly if they are married or have a regular partner, a large new study shows.

Among women who reported being dissatisfied with their sex lives, however, 57% said they wanted to have more sex, while only 8% said they would have preferred to have less.

The study is a new analysis of health information collected on more than 27,000 women ages 50 to 79 who took part in the government-funded Women's Health Initiative study.

As researchers expected, sexual activity declined with age. The main reasons women said they stopped having sex were the loss of an able partner, poor health, and poor quality of life.

The finding that many older women would prefer to have more sex was something of a surprise. Previously, doctors had believed that women stopped having sex as they got older because their sex drives fizzled.

"This is the first study that indicates that [older] women would actually like to have more sex," says Gisele Wolf-Klein, MD, director of geriatric education at the North Shore-LIJ Health System in New Hyde Park, N.Y.

"We know sexual activity decreases with age, and we do attribute that to lack of a partner, but we thought that women were kind of happy with this. That it didn't represent a major problem. Well, that does not seem to be the case," says Wolf-Klein, who was not involved in the research.

"These people are looking and interested in resuming sexual activity," she tells WebMD.

Tracking Sexual Health and Activity in Older Women

For the study, which is published in the journal Menopause, researchers looked at information collected on 27,357 women who were followed for about five to seven years.

The primary goal of that trial was to measure the benefits and risks of hormone replacement therapy (HRT) in postmenopausal women.

To that end, researchers asked women who signed up for the study questions about their sexual health and functioning.

Nearly half of the women in the study reported having sexual activity within the past year at the start of the study. That number was higher, however, nearly 70%, among women who were married or who had a steady partner.

Increasing age, lower income, lack of a sexual partner, a higher BMI, and health problems like heart attacks, depression, and arthritis made it less likely that a woman would say she had sex within the last year.

The Role of Hormone Replacement Therapy

Women who were on HRT at the beginning of the study reported higher levels of sexual activity than those who were not.

But in a finding that was puzzling to researchers, women who were assigned to take hormones as part of the study weren't significantly more likely than those taking placebo pills to continue to have sex over time.

"I was very surprised that we didn't see greater effect of hormone therapy in these women," says study researcher Margery Gass, MD, executive director of the North American Menopause Society in Mayfield Heights, Ohio.

Gass explains that since the findings of the Women's Health Initiative were announced, namely that combined estrogen and progestin therapy increased a woman's risk of heart attacks, strokes, and breast cancer, prescriptions for hormone pills and patches have declined.

But prescriptions for vaginal estrogen treatments, like creams and tablets, have increased as women look for ways to relieve vaginal dryness and loss of vaginal tissue and muscle tone, called vaginal atrophy.

"As gynecologists, we see the women who are having problems, and we are totally convinced that hormones do help women a great deal if they are experiencing dryness and discomfort with intercourse," Gass tells WebMD.

She says she thinks the finding that hormones didn't appear to have any influence in sexual function may be due to the fact that the study wasn't really designed to test hormones for that reason. And she says because most of the women in the study were married, they may have had long-established patterns of sexual activity and continued to stick to the habits despite having some discomfort.

Use It or Lose It?

Indeed, physical symptoms that could make sex uncomfortable didn't appear to slow women down. Women who reported having moderate to severe vaginal dryness were more like to report being sexually active.

Overall, 70% of women had vaginal atrophy in the study were more likely to report being sexually inactive. But Gass says it is tough to tell which problem came first.

In this case, the "use it or lose it" principle may be the key to maintaining good sexual function.

"In that regard, it's just like every other part of our body," she says. "If we want to stay in shape, playing tennis, golf, running, whatever we like to do, it's vital that we keep doing it, and this is perfectly true for intercourse as well," Gass says. "If you want to be able to be comfortable and enjoy intercourse, the best thing you can do is to maintain that activity and be consistent and regular with it."